mirror of
https://github.com/alliedmodders/amxmodx.git
synced 2024-10-18 00:06:56 +03:00
271 lines
8.9 KiB
C
271 lines
8.9 KiB
C
/*
|
|
** 2003 April 6
|
|
**
|
|
** The author disclaims copyright to this source code. In place of
|
|
** a legal notice, here is a blessing:
|
|
**
|
|
** May you do good and not evil.
|
|
** May you find forgiveness for yourself and forgive others.
|
|
** May you share freely, never taking more than you give.
|
|
**
|
|
*************************************************************************
|
|
** This file contains code used to implement the VACUUM command.
|
|
**
|
|
** Most of the code in this file may be omitted by defining the
|
|
** SQLITE_OMIT_VACUUM macro.
|
|
**
|
|
** $Id$
|
|
*/
|
|
#include "sqliteInt.h"
|
|
#include "vdbeInt.h"
|
|
#include "os.h"
|
|
|
|
#ifndef SQLITE_OMIT_VACUUM
|
|
/*
|
|
** Execute zSql on database db. Return an error code.
|
|
*/
|
|
static int execSql(sqlite3 *db, const char *zSql){
|
|
sqlite3_stmt *pStmt;
|
|
if( SQLITE_OK!=sqlite3_prepare(db, zSql, -1, &pStmt, 0) ){
|
|
return sqlite3_errcode(db);
|
|
}
|
|
while( SQLITE_ROW==sqlite3_step(pStmt) ){}
|
|
return sqlite3_finalize(pStmt);
|
|
}
|
|
|
|
/*
|
|
** Execute zSql on database db. The statement returns exactly
|
|
** one column. Execute this as SQL on the same database.
|
|
*/
|
|
static int execExecSql(sqlite3 *db, const char *zSql){
|
|
sqlite3_stmt *pStmt;
|
|
int rc;
|
|
|
|
rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
|
|
if( rc!=SQLITE_OK ) return rc;
|
|
|
|
while( SQLITE_ROW==sqlite3_step(pStmt) ){
|
|
rc = execSql(db, (char*)sqlite3_column_text(pStmt, 0));
|
|
if( rc!=SQLITE_OK ){
|
|
sqlite3_finalize(pStmt);
|
|
return rc;
|
|
}
|
|
}
|
|
|
|
return sqlite3_finalize(pStmt);
|
|
}
|
|
|
|
/*
|
|
** The non-standard VACUUM command is used to clean up the database,
|
|
** collapse free space, etc. It is modelled after the VACUUM command
|
|
** in PostgreSQL.
|
|
**
|
|
** In version 1.0.x of SQLite, the VACUUM command would call
|
|
** gdbm_reorganize() on all the database tables. But beginning
|
|
** with 2.0.0, SQLite no longer uses GDBM so this command has
|
|
** become a no-op.
|
|
*/
|
|
void sqlite3Vacuum(Parse *pParse){
|
|
Vdbe *v = sqlite3GetVdbe(pParse);
|
|
if( v ){
|
|
sqlite3VdbeAddOp(v, OP_Vacuum, 0, 0);
|
|
}
|
|
return;
|
|
}
|
|
|
|
/*
|
|
** This routine implements the OP_Vacuum opcode of the VDBE.
|
|
*/
|
|
int sqlite3RunVacuum(char **pzErrMsg, sqlite3 *db){
|
|
int rc = SQLITE_OK; /* Return code from service routines */
|
|
Btree *pMain; /* The database being vacuumed */
|
|
Btree *pTemp; /* The temporary database we vacuum into */
|
|
char *zSql = 0; /* SQL statements */
|
|
int saved_flags; /* Saved value of the db->flags */
|
|
Db *pDb = 0; /* Database to detach at end of vacuum */
|
|
char zTemp[SQLITE_TEMPNAME_SIZE+20]; /* Name of the TEMP file */
|
|
|
|
/* Save the current value of the write-schema flag before setting it. */
|
|
saved_flags = db->flags;
|
|
db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks;
|
|
|
|
sqlite3OsTempFileName(zTemp);
|
|
if( !db->autoCommit ){
|
|
sqlite3SetString(pzErrMsg, "cannot VACUUM from within a transaction",
|
|
(char*)0);
|
|
rc = SQLITE_ERROR;
|
|
goto end_of_vacuum;
|
|
}
|
|
pMain = db->aDb[0].pBt;
|
|
|
|
/* Attach the temporary database as 'vacuum_db'. The synchronous pragma
|
|
** can be set to 'off' for this file, as it is not recovered if a crash
|
|
** occurs anyway. The integrity of the database is maintained by a
|
|
** (possibly synchronous) transaction opened on the main database before
|
|
** sqlite3BtreeCopyFile() is called.
|
|
**
|
|
** An optimisation would be to use a non-journaled pager.
|
|
*/
|
|
zSql = sqlite3MPrintf("ATTACH '%q' AS vacuum_db;", zTemp);
|
|
if( !zSql ){
|
|
rc = SQLITE_NOMEM;
|
|
goto end_of_vacuum;
|
|
}
|
|
rc = execSql(db, zSql);
|
|
sqliteFree(zSql);
|
|
zSql = 0;
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
pDb = &db->aDb[db->nDb-1];
|
|
assert( strcmp(db->aDb[db->nDb-1].zName,"vacuum_db")==0 );
|
|
pTemp = db->aDb[db->nDb-1].pBt;
|
|
sqlite3BtreeSetPageSize(pTemp, sqlite3BtreeGetPageSize(pMain),
|
|
sqlite3BtreeGetReserve(pMain));
|
|
assert( sqlite3BtreeGetPageSize(pTemp)==sqlite3BtreeGetPageSize(pMain) );
|
|
rc = execSql(db, "PRAGMA vacuum_db.synchronous=OFF");
|
|
if( rc!=SQLITE_OK ){
|
|
goto end_of_vacuum;
|
|
}
|
|
|
|
#ifndef SQLITE_OMIT_AUTOVACUUM
|
|
sqlite3BtreeSetAutoVacuum(pTemp, sqlite3BtreeGetAutoVacuum(pMain));
|
|
#endif
|
|
|
|
/* Begin a transaction */
|
|
rc = execSql(db, "BEGIN EXCLUSIVE;");
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
|
|
/* Query the schema of the main database. Create a mirror schema
|
|
** in the temporary database.
|
|
*/
|
|
rc = execExecSql(db,
|
|
"SELECT 'CREATE TABLE vacuum_db.' || substr(sql,14,100000000) "
|
|
" FROM sqlite_master WHERE type='table' AND name!='sqlite_sequence'"
|
|
" AND rootpage>0"
|
|
);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
rc = execExecSql(db,
|
|
"SELECT 'CREATE INDEX vacuum_db.' || substr(sql,14,100000000)"
|
|
" FROM sqlite_master WHERE sql LIKE 'CREATE INDEX %' ");
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
rc = execExecSql(db,
|
|
"SELECT 'CREATE UNIQUE INDEX vacuum_db.' || substr(sql,21,100000000) "
|
|
" FROM sqlite_master WHERE sql LIKE 'CREATE UNIQUE INDEX %'");
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
|
|
/* Loop through the tables in the main database. For each, do
|
|
** an "INSERT INTO vacuum_db.xxx SELECT * FROM xxx;" to copy
|
|
** the contents to the temporary database.
|
|
*/
|
|
rc = execExecSql(db,
|
|
"SELECT 'INSERT INTO vacuum_db.' || quote(name) "
|
|
"|| ' SELECT * FROM ' || quote(name) || ';'"
|
|
"FROM sqlite_master "
|
|
"WHERE type = 'table' AND name!='sqlite_sequence' "
|
|
" AND rootpage>0"
|
|
|
|
);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
|
|
/* Copy over the sequence table
|
|
*/
|
|
rc = execExecSql(db,
|
|
"SELECT 'DELETE FROM vacuum_db.' || quote(name) || ';' "
|
|
"FROM vacuum_db.sqlite_master WHERE name='sqlite_sequence' "
|
|
);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
rc = execExecSql(db,
|
|
"SELECT 'INSERT INTO vacuum_db.' || quote(name) "
|
|
"|| ' SELECT * FROM ' || quote(name) || ';' "
|
|
"FROM vacuum_db.sqlite_master WHERE name=='sqlite_sequence';"
|
|
);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
|
|
|
|
/* Copy the triggers, views, and virtual tables from the main database
|
|
** over to the temporary database. None of these objects has any
|
|
** associated storage, so all we have to do is copy their entries
|
|
** from the SQLITE_MASTER table.
|
|
*/
|
|
rc = execSql(db,
|
|
"INSERT INTO vacuum_db.sqlite_master "
|
|
" SELECT type, name, tbl_name, rootpage, sql"
|
|
" FROM sqlite_master"
|
|
" WHERE type='view' OR type='trigger'"
|
|
" OR (type='table' AND rootpage=0)"
|
|
);
|
|
if( rc ) goto end_of_vacuum;
|
|
|
|
/* At this point, unless the main db was completely empty, there is now a
|
|
** transaction open on the vacuum database, but not on the main database.
|
|
** Open a btree level transaction on the main database. This allows a
|
|
** call to sqlite3BtreeCopyFile(). The main database btree level
|
|
** transaction is then committed, so the SQL level never knows it was
|
|
** opened for writing. This way, the SQL transaction used to create the
|
|
** temporary database never needs to be committed.
|
|
*/
|
|
if( rc==SQLITE_OK ){
|
|
u32 meta;
|
|
int i;
|
|
|
|
/* This array determines which meta meta values are preserved in the
|
|
** vacuum. Even entries are the meta value number and odd entries
|
|
** are an increment to apply to the meta value after the vacuum.
|
|
** The increment is used to increase the schema cookie so that other
|
|
** connections to the same database will know to reread the schema.
|
|
*/
|
|
static const unsigned char aCopy[] = {
|
|
1, 1, /* Add one to the old schema cookie */
|
|
3, 0, /* Preserve the default page cache size */
|
|
5, 0, /* Preserve the default text encoding */
|
|
6, 0, /* Preserve the user version */
|
|
};
|
|
|
|
assert( 1==sqlite3BtreeIsInTrans(pTemp) );
|
|
assert( 1==sqlite3BtreeIsInTrans(pMain) );
|
|
|
|
/* Copy Btree meta values */
|
|
for(i=0; i<sizeof(aCopy)/sizeof(aCopy[0]); i+=2){
|
|
rc = sqlite3BtreeGetMeta(pMain, aCopy[i], &meta);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
rc = sqlite3BtreeUpdateMeta(pTemp, aCopy[i], meta+aCopy[i+1]);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
}
|
|
|
|
rc = sqlite3BtreeCopyFile(pMain, pTemp);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
rc = sqlite3BtreeCommit(pTemp);
|
|
if( rc!=SQLITE_OK ) goto end_of_vacuum;
|
|
rc = sqlite3BtreeCommit(pMain);
|
|
}
|
|
|
|
end_of_vacuum:
|
|
/* Restore the original value of db->flags */
|
|
db->flags = saved_flags;
|
|
|
|
/* Currently there is an SQL level transaction open on the vacuum
|
|
** database. No locks are held on any other files (since the main file
|
|
** was committed at the btree level). So it safe to end the transaction
|
|
** by manually setting the autoCommit flag to true and detaching the
|
|
** vacuum database. The vacuum_db journal file is deleted when the pager
|
|
** is closed by the DETACH.
|
|
*/
|
|
db->autoCommit = 1;
|
|
|
|
if( pDb ){
|
|
sqlite3MallocDisallow();
|
|
sqlite3BtreeClose(pDb->pBt);
|
|
sqlite3MallocAllow();
|
|
pDb->pBt = 0;
|
|
pDb->pSchema = 0;
|
|
}
|
|
|
|
sqlite3OsDelete(zTemp);
|
|
strcat(zTemp, "-journal");
|
|
sqlite3OsDelete(zTemp);
|
|
sqliteFree( zSql );
|
|
sqlite3ResetInternalSchema(db, 0);
|
|
|
|
return rc;
|
|
}
|
|
#endif /* SQLITE_OMIT_VACUUM */
|